Compositor Effects in Video Sequence Editor. Adjust global brightness/contrast
Bloom. White Range bleeds and blends onto other areas




Compositor and Render windows in Blender
The 3D View Composited Rendered image can be input to VSE.




Above image shows the Render Layers allows the user to select another scene.  The Input node in yellow is for a sequence of images. It is not yet connected but it can replace the Render Layers Node as input. 88 seconds of work or less.


The VSE rendered image can be input to Compositor.  Any Rendered image can be Composited in a different Scene.  Similar to GIMP or Photo????
Some Blender Users may need to create an image sequence in intermediate stages.   Next those images are used again in another scene.  This may or may not be acceptable.  The question of one scene using another scene may arise, or these steps can be manual.  
Note the Render Layers Node has an entry for a Scene.  Thus one scene can reference another scene.  This answer will not focus on that useful feature of Blender.  That may be a new question about that feature.
[Scene A] may produce a sequence of PNG or other format images on some storage device.  [Scene B] can read those images and produce new image to write to storage device. Device is hard disk, flash drive or other.  [Scene B] might have a text object, which is not rendered, reading [See The compositor]
Click image to see larger image.
Please verify and improve Compositor Nodes





Yellow arrow shows Compositor is enabled